Controlling Spring Length in Assembly

[ssmithdigilab]

I want to control the length of a spring in an assembly by having that length related to the distance between two components (one static and one movable).

I remember back in my Pro/E days that I could create an equation that made the length of my helix equal to a measurement of the distance between the two components that the spring was between. Then when I moved one of the components the spring would compress/extend realistically.

Is something similar possible in SolidWorks? I have searched the site extensively and haven't found a solution to this exact problem.

For reference, I have created the spring by using the following method. I started by offsetting a plane from the right plane in the model. I then created a circle on the right plane to represent the OD of the spring. I then created a helix using this circle (Height and Revolution). Then I created a circle on the front plane for the profile. Next I swept the profile along the helix. Lastly I created an equation equating the length of the helix to the distance between the planes. Therefore, I can change the distance between the planes and my spring length updates nicely.

In my assembly I mated the right plane to the static component and mated the offset plane to the movable component. I would like to be able to drag the movable component and have the spring update either dynamically or upon rebuild. Unfortunately, once I mate the spring to the movable component, it no longer becomes movable.

Any help would be greatly appreciated.

 

[CorBlimeyLimey]

Lots of video tutorials HERE

 

[rgrayclamps]

Hi, ssmithdigilab:

Use top-down approach. Create your spring with incontext between two components.

Good luck!

Alex

 

[Eltron]

Check faq559-1492 part VI. Instead of a cut for threads do a swept boss for a spring and do it in the context of an assembly.

Dan

http://www.eltronresearch.com

Dan's Blog

 

[ssmithdigilab]

I am not familiar with the term "in the context of an assembly". I have seen people mention "in-context" a number of times and don't know what that means. Can someone please explain this to me and describe how to use it? I have searched the help file and haven't been able to figure it out.

 

[Eltron]

From the SW Help file:

External vs. Defined in Context
External – A relation that is "External" is a relation between a sketch entity and something outside of that sketch. This thing can be an edge or vertex within the same model or it can be an edge or vertex within a different model within an assembly.

Defined in Context – A relation that is "Defined in Context" is a relation between a sketch entity in one part and some entity in another part. This relation occurs within the context of the assembly.

Entities that are "Defined in Context" are listed as "External" because they have relations outside of the sketch. However, not all "External" relations are "Defined in Context" because they may be relations within the same part file.

Dan

http://www.eltronresearch.com

Dan's Blog